We consider situations in which public charter school lotteries are neither universally conducted nor consistently documented. Such lotteries produce “broken” Randomized Control Trials, but provide opportunities to assess the internal validity of quasi-experimental research designs. Here, we...

In randomized controlled trials, it is common for attrition rates to differ by lottery status, jeopardizing the identification of causal effects. Inverse probability weighting methods (Hirano et al, 2003; Busso et al., 2014) and estimation of informative bounds for the treatment effects (e.g. Lee, 2009;...